Embedded Linux Based Research And Design Of The Harmonic Detection Mechanism

Modern society, energy is indispensable subsistence for human beings to develop. Development of energy, energy and the environment are the common concern of the world and all human beings as well as has become important problems of social economic development in current China. Since the 1960s, with the widespread use of power electronic technology in various fields, the pollution of power harmonics has been becoming increasingly serious. Governance of power harmonics should be done immediately. Therefore, it’s very significant to detect and analyze the power harmonics.Based on the Linux operating system, detecting device of embedded harmonics takes the S3C2440 as the processor which collects three-phase voltage and current of electrical network. By improving the FFT algorithm, signs of collected voltage and current can be calculated in parameter, and the results will be shown on the screen of LCD. Meanwhile, the statistics can be uploaded to users through the IEC-5-104 protocol.Major work:1) Make a further research on theory of harmonic detection to deal with FFT calculation using window functions for promoting the speed of FFT calculation, as well as reduce the spectrum leakage and fence effect.2) Provide schematic diagrams of hardware design of main circuits in detail, including signal acquisition and data processing, data communication and data storage, as well as hardware circuits of Human-Computer Interaction.3) Finish the software design depending on hardware system, and transplant Linux kernel and hardware driver under the Linux operating system. Finish making the U-BOOT and root file system. Write application, mainly including NIC program, A/D acquisition program, FFT calculation program and Human-Computer Interaction.4) Detect the device so as to imitate making electrical signal connection device with harmonics, testify FFT calculation and the device.